Double-UV anti-reflection film and preparation method thereof

Abstract

This invention discloses a dual anti-UV antireflective film and its preparation method. The dual anti-UV antireflective film includes an anti-UV optical film, an anti-UV curing coating formed on the surface of the anti-UV optical film, and a low-refractive-index anti-UV coating formed on the surface of the anti-UV curing coating. This invention can effectively prevent problems such as coating peeling and decreased mechanical properties caused by rapid material aging. The ultraviolet absorber prevents ultraviolet rays from penetrating the resin polymer and causing internal degradation, thus significantly slowing down the degradation rate. The light stabilizer, as a free radical scavenger, can interrupt the oxidation chain reaction in the photo-oxidation process, significantly reducing the degradation rate of the resin polymer and preventing material degradation that leads to poor appearance and mechanical properties. The inorganic particles added to the coating solution can also act as light shielding agents to absorb or reflect ultraviolet rays, preventing them from penetrating the coating.

Description

Technical Field

[0001] This invention relates to the field of antireflective film materials, and in particular to a dual anti-UV antireflective film and its preparation method. Background Technology

[0002] In recent years, transparent plastics such as polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), and polycarbonate (PC) have been widely used in electronic displays due to their low cost. Although they possess excellent optical properties, they typically require a hard, scratch-resistant coating to improve their impact and abrasion resistance. Furthermore, an anti-reflective coating with fingerprint-resistant properties is often applied to the substrate to minimize unwanted reflections from the substrate. Anti-reflective films utilize the destructive interference between reflected light at different interfaces of the thin film coating to reduce the overall reflectivity of the substrate material, thereby reducing external light reflection and surface contamination, and improving the contrast, readability, and image quality of the electronic display.

[0003] Nowadays, people are increasingly reliant on electronic products, inevitably using consumer electronics such as mobile phones and tablets outdoors frequently, significantly increasing their exposure to ultraviolet (UV) radiation. Prolonged outdoor exposure can damage electronic displays, causing color distortion, fading, yellowing, cracking, peeling, embrittlement, and delamination, affecting screen clarity and brightness. When coatings or films are exposed outdoors, factors such as moisture, heat, and UV radiation can cause their degradation. UV radiation and moisture can chemically degrade film-forming resins, and these degradation reactions often accelerate at higher temperatures.

[0004] Patent CN109557604B discloses an anti-ultraviolet antireflective film and its application. The film is made by alternately stacking layers of dielectric materials with different refractive indices. By utilizing the different reflection and refraction effects of light waves with different wavelengths at the interface between the different dielectric material layers, it has an excellent reflection effect on ultraviolet light; however, its ultraviolet light transmittance is still as high as 5.9%.

[0005] Therefore, it is now necessary to improve existing technologies to provide more reliable solutions. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a dual anti-UV antireflective film and its preparation method, in order to address the shortcomings of the prior art.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: In the first aspect of the present invention, a dual anti-UV antireflective film is provided, comprising an anti-UV optical film, an anti-UV curing coating formed on the surface of the anti-UV optical film, and a low refractive index anti-UV coating formed on the surface of the anti-UV curing coating.

[0008] The UV-resistant curing coating is obtained by coating the surface of the UV-resistant optical film with a UV-resistant curing liquid and then curing it. The UV-resistant curing liquid comprises the following raw material components by weight: 6-12 parts by weight of acrylate monomers, 15-30 parts by weight of acrylic resin oligomers, 3-6 parts by weight of first inorganic particles, 60-80 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator.

[0009] Preferably, the low-refractive-index anti-UV coating is obtained by applying a low-refractive-index anti-UV liquid onto the surface of the anti-UV curing coating and then curing it. The low-refractive-index anti-UV liquid comprises the following raw material components by weight: 3-7 parts by weight of acrylate monomers, 5-11 parts by weight of fluorinated modified acrylic resin oligomers, 2-4 parts by weight of second inorganic particles, 100-200 parts by weight of solvent, 1-2 parts by weight of UV absorber, 1-2 parts by weight of light stabilizer, and 2-3 parts by weight of photoinitiator.

[0010] Preferably, the acrylic resin oligomer is a mixture of one or more of epoxy acrylate, polyurethane acrylate, polyester acrylate and polyether acrylate.

[0011] Preferably, the first inorganic particle is one or a mixture of zirconium oxide or titanium oxide.

[0012] Preferably, the acrylate monomer is one or a mixture of several of the following: trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trihydroxypropane tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and neopentyl glycol diacrylate.

[0013] Preferably, the solvent is one or a mixture of several of ethyl acetate, n-butyl acetate, methyl isobutyl ketone, and isopropanol;

[0014] The ultraviolet absorber is one or a mixture of several of the following: 2-(2ˊ-hydroxy-5ˊ-methylphenyl)benzotriazole, 2-hydroxy-4-methoxybenzophenone, 2,4,6-tris(2ˊn-butoxyphenyl)-1,3,5-triazine, 2-(2ˊ-hydroxy-3ˊ,5ˊ-di-tert-butylphenyl)-5-chlorobenzotriazole and 2,4-dihydroxybenzophenone;

[0015] The light stabilizer is one or a mixture of several of the following: tris(1,2,2,6,6-pentamethylpiperidinyl) phosphite, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, and hexamethylphosphoric triamine.

[0016] The photoinitiator is one or a mixture of 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and 1,1'-(methylenedi-4,1-phenylene)bis[2-hydroxy-2-methyl-1-propanone].

[0017] Preferably, the second inorganic particle is a hollow mesoporous silica microsphere.

[0018] A second aspect of the present invention provides a method for preparing the dual anti-UV antireflective film as described above, comprising the following steps:

[0019] S1. Preparation of UV-resistant curing coating:

[0020] Mix 6-12 parts by weight of acrylate monomers, 15-30 parts by weight of acrylic resin oligomers, 3-6 parts by weight of first inorganic particles, 60-80 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator, and stir evenly to obtain UV-resistant curing coating liquid.

[0021] S2. Apply the anti-UV curing liquid obtained in step S1 onto the anti-UV optical film, and after drying and UV curing, form an anti-UV curing coating on the anti-UV optical film.

[0022] S3. Preparation of low refractive index UV-resistant coating:

[0023] Mix 3-7 parts by weight of acrylate monomers, 5-11 parts by weight of fluorinated modified acrylic resin oligomers, 2-4 parts by weight of second inorganic particles, 100-200 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator, stir evenly to obtain a low refractive index anti-UV coating liquid.

[0024] S4. Apply the low-refractive-index anti-UV coating liquid prepared in step S3 onto the anti-UV hardening coating formed in step S2. After drying and UV curing, a low-refractive-index anti-UV coating is formed on the anti-UV hardening coating to obtain the double anti-UV antireflective film.

[0025] Preferably, the anti-UV optical film is selected from PET, PMMA, PC, TAC or SRF film with anti-UV function;

[0026] The thickness of the UV-resistant curing coating is 2–6 μm, and the thickness of the low-refractive-index UV-resistant coating is 90–110 nm.

[0027] Preferably, the drying temperature in steps S2 and S4 is 90–110°C, and the drying time is 1–3 min.

[0028] The beneficial effects of this invention are:

[0029] This invention provides a dual anti-UV antireflective film by sequentially layering an anti-UV curing coating and a low-refractive-index anti-UV coating onto an anti-UV optical film. This film effectively prevents problems such as coating peeling and decreased mechanical properties caused by rapid material aging. The UV absorber in the anti-UV curing coating rapidly absorbs UV light from the environment, preventing chromophores in the material from absorbing UV energy and converting the absorbed light energy into harmless heat. The UV absorber also prevents UV rays from penetrating the resin polymer and causing internal degradation, significantly slowing down the degradation rate. During photo-oxidation, the light stabilizer acts as a free radical scavenger. It can interrupt the oxidation chain reaction in the photo-oxidation process, significantly reduce the degradation rate of resin polymers, and prevent the material from deteriorating due to degradation, resulting in poor appearance and mechanical properties. The inorganic particles added to the coating liquid can also act as light shielding agents to absorb or reflect ultraviolet rays, preventing them from penetrating into the coating. The anti-UV optical film can further inhibit ultraviolet rays from damaging the resin polymers, improve the anti-aging performance of the product, and extend its service life. The dual anti-UV anti-reflective film of this invention can increase transmittance and reduce reflectance, thereby reducing image distortion and glare, allowing users to enjoy clearer image quality. The added fluorinated modified resin can improve abrasion resistance and extend service life.

[0030] In this invention, the multifunctional acrylate monomers added to the curing and antireflective coatings exhibit high reactivity, high crosslinking density, high hardness of the cured film, and excellent tensile strength, thereby improving the photocuring efficiency and crosslinking density of the curing and antireflective films. The ultraviolet absorber acts as a filter for ultraviolet light, absorbing most of the high-energy, harmful radiation and releasing it as heat, significantly slowing down the degradation rate of the resin polymer. After the polymer dissociates under light radiation to generate free radicals, the light stabilizer captures these active free radicals, making them stable compounds and greatly delaying the aging of the polymer material. The disadvantage of the ultraviolet absorber is that it cannot protect the entire thickness of the coating; it requires a limited path length to achieve significant absorbance, meaning its protective ability weakens the closer it is to the coating surface. In contrast, the effect of the light stabilizer does not change with the decrease in coating thickness. By compounding the ultraviolet absorber and the light stabilizer, there is a mutual protective effect between them, exhibiting a synergistic effect, thus achieving better protective performance.

[0031] In this invention, the inorganic particles in the coating liquid can not only increase the hardness of the coating and reduce the reflectivity of the coating, but also absorb or reflect ultraviolet rays, reduce the direct radiation of light into the interior of the resin polymer, reduce the harm of ultraviolet rays, and further inhibit photo-oxidative degradation.

[0032] Since ultraviolet light absorbers can absorb ultraviolet light, they can affect the initiation efficiency of photoinitiators. In this invention, the proportion of photoinitiator added to monomers and oligomers is increased to 6-9% to prevent the coating from curing incompletely due to too low an amount of initiator, which would affect the coating's adhesion and wear resistance. At the same time, it prevents the formation of reaction byproducts due to too high an amount of initiator, which could affect the photoinitiated polymerization or curing effect.

[0033] In this invention, the fluorinated modified acrylic resin oligomer can form a smooth fluorine film on the coating surface after curing. This film not only prevents the adhesion of water and oil and maintains excellent slip properties, but also protects the surface from scratches, greatly enhances the friction resistance, and extends the service life of the product. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to embodiments, so that those skilled in the art can implement it based on the description.

[0035] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0036] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials and reagents used in the following examples are commercially available. For examples where specific conditions are not specified, conventional conditions or conditions recommended by the manufacturer are followed. For reagents or instruments whose manufacturers are not specified, they are all commercially available products.

[0037] The present invention provides a dual anti-UV antireflective film, comprising an anti-UV optical film, an anti-UV curing coating formed on the surface of the anti-UV optical film, and a low-refractive-index anti-UV coating formed on the surface of the anti-UV curing coating.

[0038] In a preferred embodiment, the UV-resistant curing coating is obtained by coating the surface of the UV-resistant optical film with a UV-resistant curing liquid and then curing it. The UV-resistant curing liquid includes the following raw material components by weight: 6-12 parts by weight of acrylate monomers, 15-30 parts by weight of acrylic resin oligomers, 3-6 parts by weight of first inorganic particles, 60-80 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer, and 2-3 parts by weight of photoinitiator.

[0039] In a preferred embodiment, the low-refractive-index anti-UV coating is obtained by coating the surface of the anti-UV curing coating with a low-refractive-index anti-UV liquid and then curing it. The low-refractive-index anti-UV liquid includes the following raw material components by weight: 3 to 7 parts by weight of acrylate monomers, 5 to 11 parts by weight of fluorinated modified acrylic resin oligomers, 2 to 4 parts by weight of second inorganic particles, 100 to 200 parts by weight of solvent, 1 to 2 parts by weight of ultraviolet light absorber, 1 to 2 parts by weight of light stabilizer and 2 to 3 parts by weight of photoinitiator.

[0040] In a preferred embodiment, the acrylic resin oligomer is a mixture of one or more of epoxy acrylate, polyurethane acrylate, polyester acrylate and polyether acrylate.

[0041] In a preferred embodiment, the first inorganic particle is one or a mixture of two of zirconium oxide or titanium oxide.

[0042] In a preferred embodiment, the acrylate monomer is one or a mixture of several of the following: trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trihydroxypropane tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and neopentyl glycol diacrylate.

[0043] In a preferred embodiment, the solvent is one or a mixture of several of ethyl acetate, n-butyl acetate, methyl isobutyl ketone, and isopropanol.

[0044] In a preferred embodiment, the ultraviolet absorber is one or a mixture of several of 2-(2ˊ-hydroxy-5ˊ-methylphenyl)benzotriazole, 2-hydroxy-4-methoxybenzophenone, 2,4,6-tris(2ˊn-butoxyphenyl)-1,3,5-triazine, 2-(2ˊ-hydroxy-3ˊ,5ˊ-di-tert-butylphenyl)-5-chlorobenzotriazole and 2,4-dihydroxybenzophenone.

[0045] In a preferred embodiment, the light stabilizer is one or a mixture of several of the following: tris(1,2,2,6,6-pentamethylpiperidinyl)phosphite, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, and hexamethylphosphoric triamine.

[0046] In a preferred embodiment, the photoinitiator is one or a mixture of 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and 1,1'-(methylenedi-4,1-phenylene)bis[2-hydroxy-2-methyl-1-propanone].

[0047] In a preferred embodiment, the second inorganic particle is a hollow mesoporous silica microsphere.

[0048] The present invention also provides a method for preparing the above-mentioned dual anti-UV antireflective film, comprising the following steps:

[0049] S1. Preparation of UV-resistant curing coating:

[0050] Mix 6-12 parts by weight of acrylate monomers, 15-30 parts by weight of acrylic resin oligomers, 3-6 parts by weight of first inorganic particles, 60-80 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator, and stir evenly to obtain UV-resistant curing coating liquid.

[0051] S2. Apply the anti-UV curing liquid obtained in step S1 onto the anti-UV optical film, and after drying and UV curing, form an anti-UV curing coating on the anti-UV optical film.

[0052] S3. Preparation of low refractive index UV-resistant coating:

[0053] Mix 3-7 parts by weight of acrylate monomers, 5-11 parts by weight of fluorinated modified acrylic resin oligomers, 2-4 parts by weight of second inorganic particles, 100-200 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator, stir evenly to obtain a low refractive index anti-UV coating liquid.

[0054] S4. Apply the low-refractive-index anti-UV coating liquid prepared in step S3 onto the anti-UV hardening coating formed in step S2. After drying and UV curing, a low-refractive-index anti-UV coating is formed on the anti-UV hardening coating to obtain a double anti-UV anti-reflection film.

[0055] In a preferred embodiment, the thickness of the UV-resistant curing coating is 2–6 μm, and the thickness of the low-refractive-index UV-resistant coating is 90–110 nm.

[0056] In a preferred embodiment, the drying temperature in steps S2 and S4 is 90–110°C, and the drying time is 1–3 min.

[0057] In a preferred embodiment, the stirring time in steps S1 and S3 is 1 to 2 hours, and the stirring speed is 600 to 800 rpm.

[0058] In a preferred embodiment, the anti-UV optical film is selected from PET, PMMA, PC, TAC or SRF films with anti-UV function.

[0059] When materials are exposed to the outdoors, ultraviolet radiation triggers a reaction, atmospheric oxygen participates in chemical degradation, and chromophores in the material absorb radiation photons, initiating degradation. Besides photo-oxidation, especially under high-temperature sunlight, when the coating temperature rises, the film-forming resin in the coating can also undergo hydrolytic degradation. This invention obtains a dual anti-UV antireflective film by sequentially coating an anti-UV curing solution and a low-refractive-index anti-UV solution onto an anti-UV optical film. This effectively prevents problems such as coating peeling and decreased mechanical properties caused by rapid material aging. The ultraviolet absorber in the anti-UV curing solution can quickly absorb ultraviolet light from the environment, preventing the chromophores in the material from absorbing ultraviolet energy, and converting the absorbed light energy into harmless heat. The ultraviolet absorber can also prevent ultraviolet light from penetrating the resin polymer and causing internal degradation, significantly slowing down the degradation rate. During photo-oxidation, the light stabilizer acts as... Free radical scavengers can interrupt oxidation chain reactions, significantly reducing the degradation rate of resin polymers and preventing material degradation that leads to poor appearance and mechanical properties. Inorganic particles added to the coating can also act as light shielding agents to absorb or reflect ultraviolet rays, preventing them from penetrating the coating. Anti-UV optical films can further inhibit ultraviolet rays from damaging resin polymers, improving the product's anti-aging performance and extending its service life. Anti-reflective films can increase transmittance and reduce reflectance, thereby reducing image distortion and glare, allowing users to enjoy clearer image quality. The added fluorinated modified resin can improve abrasion resistance and extend service life.

[0060] The above is the general concept of the present invention. Based on this, detailed embodiments and comparative examples are provided below to further illustrate the present invention.

[0061] Example 1

[0062] A method for preparing the dual anti-UV antireflective film as described above includes the following steps:

[0063] S1. Preparation of UV-resistant curing coating:

[0064] Nine parts by weight of dipentaerythritol hexaacrylate, 22 parts by weight of polyurethane acrylate, 4.5 parts by weight of zirconium oxide particles (SZR-CW, particle size 25 nm, Sakai Chemical Industry Co., Ltd.), 20 parts by weight of ethyl acetate, 50 parts by weight of methyl isobutyl ketone, 1.5 parts by weight of 2-(2ˊ-hydroxy-5ˊ-methylphenyl)benzotriazole, 1.5 parts by weight of tris(1,2,2,6,6-pentamethylpiperidinyl) phosphite, and 2.5 parts by weight of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added sequentially to a reaction vessel and stirred at 700 rpm for 1.5 h to obtain an anti-UV curing coating solution.

[0065] S2. Apply the UV-resistant curing coating obtained in step S1 onto the UV-resistant optical PET film (XF7LA7, 50μm thick, Toray Industries, Inc.), dry at 100°C for 2 min, and then UV-cur (UV energy 400mJ / cm² under a high-pressure mercury lamp). 2 A UV-resistant hardening coating with a thickness of 4 μm is formed on the UV-resistant optical film;

[0066] S3. Preparation of low refractive index UV-resistant coating:

[0067] Five parts by weight of dipentaerythritol hexaacrylate, eight parts by weight of fluorinated modified acrylic resin (2,2,3,3,4,4,5,5,6,6,7,7-dodecylfluoroheptyl acrylate, D154301, Shanghai Aladdin), three parts by weight of hollow mesoporous silica microspheres (ELCOM JX-1009SIV, particle size 30nm, Nichibukai Chemical Co., Ltd.), 40 parts by weight of ethyl acetate, 120 parts by weight of methyl isobutyl ketone, 1.5 parts by weight of 2-(2ˊ-hydroxy-5ˊ-methylphenyl)benzotriazole, 1.5 parts by weight of tris(1,2,2,6,6-pentamethylpiperidinyl) phosphite, and 2.5 parts by weight of 1-hydroxycyclohexylphenyl ketone were added sequentially to a reaction vessel and stirred and dispersed at 700 rpm for 1.5 h to obtain a low refractive index anti-UV coating solution.

[0068] S4. Apply the low-refractive-index anti-UV coating prepared in step S3 onto the anti-UV hardening coating formed in step S2, dry at 100℃ for 2 min, and then UV cure (UV energy 600 mJ / cm² under nitrogen protection and a high-pressure mercury lamp). 2 A low-refractive-index anti-UV coating is formed on the anti-UV hardening coating to obtain the dual anti-UV anti-reflective film with a thickness of 100 nm.

[0069] Example 2

[0070] This example is basically the same as Example 1, except that the acrylate monomer added to the UV-resistant curing coating and the low-refractive-index UV-resistant coating is dipentaerythritol pentaacrylate.

[0071] Example 3

[0072] This example is basically the same as Example 1, except that the acrylate monomer added to the UV-resistant curing coating and the low-refractive-index UV-resistant coating is trihydroxypropane tetraacrylate.

[0073] Example 4

[0074] This example is basically the same as Example 1, except that the first inorganic particle added to the UV-resistant curing coating is titanium dioxide (RTTMIBK15WT%-N24, particle size 50nm, Tokyo Chemical Industry Co., Ltd.).

[0075] Example 5

[0076] This example is basically the same as Example 1, except that the UV absorber added to the UV-resistant curing coating and the low-refractive-index UV-resistant coating is 2,4,6-tris(2ˊn-butoxyphenyl)-1,3,5-triazine.

[0077] Example 6

[0078] This example is basically the same as Example 1, except that the light stabilizer added to the UV-resistant curing coating and the low-refractive-index UV-resistant coating is 4-benzoyloxy-2,2,6,6-tetramethylpiperidine.

[0079] Example 7

[0080] This example is basically the same as Example 1, except that the photoinitiator added to the UV-resistant curing coating and the low-refractive-index UV-resistant coating is 1,1'-(methylenedi-4,1-phenylene)bis[2-hydroxy-2-methyl-1-propanone].

[0081] Comparative Example 1

[0082] This example is basically the same as Example 1, except that the UV absorber (2-(2ˊ-hydroxy-5ˊ-methylphenyl)benzotriazole) was not added to the UV-resistant curing coating and the low-refractive-index UV-resistant coating.

[0083] Comparative Example 2

[0084] This example is basically the same as Example 1, except that no light stabilizer (tris(1,2,2,6,6-pentamethylpiperidinyl)phosphite) was added to the UV-resistant curing coating and the low-refractive-index UV-resistant coating.

[0085] Comparative Example 3

[0086] This example is basically the same as Example 1, except that a regular optical PET film (U483, 50 μm thick, Toray Industries, Inc.) without UV protection is used instead of the UV-resistant optical PET film in Example 1.

[0087] Comparative Example 4

[0088] This example is basically the same as Example 1, except that the low refractive index anti-UV coating uses unfluorinated conventional acrylic resin (CN9006NS acrylate oligomer, Sartoma) instead of the fluorinated acrylic resin in Example 1.

[0089] Comparative Example 5

[0090] This example is basically the same as Example 1, except that the amount of photoinitiator 1-hydroxycyclohexylphenyl ketone added in both the UV-resistant curing coating and the low-refractive-index UV-resistant coating is 1.9 parts by weight.

[0091] Comparative Example 6

[0092] This example is basically the same as Example 1, except that the amount of 1-hydroxycyclohexylphenyl ketone added to both the UV-resistant curing coating and the low-refractive-index UV-resistant coating is 3.1 parts by weight.

[0093] The products prepared in Examples 1-7 and Comparative Examples 1-6 were subjected to the following performance tests:

[0094] (1) Transmittance / Haze: The transmittance and haze of the thin film sample were tested in transmission mode using a spectrophotometer.

[0095] (2) Reflectivity: The thin film sample was cut into 50mm*50mm pieces, and the sample substrate was attached to the surface of the screen module. The reflectivity at 550nm was tested in reflection mode.

[0096] (3) Pencil hardness: Place the film sample on a horizontal and stable surface, insert the ground MITSU-BISHI UNI test pencil into the test instrument, with the pencil lead tip in contact with the surface to be tested at a 45° angle, draw 5 parallel lines with a length of 5cm under a load of 1000g, and then observe the optical film coating under a fluorescent lamp. The hardest pencil number is the scratch hardness when there is no scratch or whitening throughout the process.

[0097] (4) Adhesion: Use a 1*1cm cross-cutting tool to make 10×10 grids at 1mm intervals on the surface of the film sample. Attach 3M 600 tape to the test grid and press it flat with a roller to ensure good contact between the tape and the coating. After standing for 90 seconds, quickly tear off the tape and check the coating peeling condition.

[0098] (5) Elongation at break: The film sample was cut into strips with dimensions of 10mm*200mm. The strips were fixed between the upper and lower clamps of the tensile testing machine with a clamp spacing of 50mm. The tensile testing machine was started for testing. The machine was stopped when the test strip reached the predetermined test strain. The strips were removed to observe whether there were cracks in the coating and the results were recorded.

[0099] (6) Solar radiation: The thin film sample was attached to a glass cover plate and placed in a test chamber. A cycle of 20 hours of light and 4 hours of darkness was conducted under simulated solar radiation and temperature conditions (light conditions: chamber temperature 40℃, blackboard temperature 50℃, humidity 35%, lamp irradiance at 340nm wavelength 0.55W / m²). 2The wavelength range is 300-800nm; under dark conditions (temperature set at 40℃, humidity at 50%), 5 cycles are tested. After the test, the adhesion test is performed after the sample returns to room temperature.

[0100] (7) Steel wool abrasion resistance: Attach the film sample to the glass cover plate and install it on the abrasion tester. Apply a load of 1000g to the test surface of the sample. Use Bonstar#0000 steel wool with a test head area of ​​20*20mm. Test at a speed of 40cycle / min and a stroke of about 40mm. After the specified number of cycles, observe under D65 light source for scratches or marks. If there are more than 5 scratches or marks, it is judged as NG.

[0101] The test results of the dual anti-UV antireflective films obtained in the examples and comparative examples are shown in Table 1 below:

[0102] Table 1

[0103]

[0104]

[0105] As shown in the table above, the dual anti-UV antireflective films prepared in each embodiment have the characteristics of high visible light transmittance, low haze, low ultraviolet light transmittance, low reflectance, high pencil hardness, good coating adhesion, high elongation at break, and high wear resistance. Furthermore, the coating adhesion performance is good even after prolonged exposure to ultraviolet light, and the elongation at break does not decrease significantly. Example 1 has a visible light transmittance of 94.7%, a haze of 0.39%, an ultraviolet light transmittance of 1.9% at 380nm, a reflectance of 0.64% at 550nm, a pencil hardness of 1H, a cross-cut hardness of 5B, a cross-cut hardness of 5B after solar radiation, an elongation at break of 6.0%, an elongation at break of 4.8% after solar radiation, and a steel wool abrasion resistance of 2300 cycles (OK).

[0106] Compared to Comparative Example 1, Example 1 did not contain any UV absorbers in its UV-resistant curing coating and low-refractive-index UV-resistant coating. The UV transmittance at 380 nm was significantly improved, and the cross-sectional area B (0.5%) and elongation at break after solar radiation were significantly reduced. Compared to Comparative Example 2, Example 1 did not contain any light stabilizers in its UV-resistant curing liquid and low-refractive-index UV-resistant coating. The UV transmittance at 380 nm was not significantly improved, and the cross-sectional area B (0.5%) and elongation at break after solar radiation were significantly reduced. Compared to Comparative Example 3, Example 1 did not contain any UV-resistant optical film substrate. The UV transmittance at 380 nm was significantly improved, and the cross-sectional area B (2.5%) and elongation at break after solar radiation were significantly reduced. Compared to Comparative Example 4, Example 1 did not contain any unfluorinated modified resin in its low-refractive-index coating. The steel wool abrasion resistance was only 10 times before it was OK. Compared to Comparative Example 5, Example 1 showed a significant decrease in cross-section 1B and elongation at break after solar radiation due to the addition of 1.9 parts by weight of photoinitiator to the UV-resistant curing liquid and low-refractive-index UV-resistant coating liquid in Comparative Example 5. Compared to Comparative Example 6, Example 1 showed a significant decrease in cross-section 2B and elongation at break after solar radiation due to the addition of 3.1 parts by weight of photoinitiator to the UV-resistant curing liquid and low-refractive-index UV-resistant coating liquid in Comparative Example 6.

[0107] The comparison between the above examples and comparative examples shows that: using only UV absorbers, light stabilizers or substrates with anti-UV function is not ideal. The synergistic effect of UV absorbers, light stabilizers and anti-UV films can effectively reduce the damage caused by ultraviolet rays passing through the resin polymer and prevent the material from aging too quickly. Adding fluorinated modified resin can significantly improve the friction resistance of the anti-reflective film. Too little or too much photoinitiator will affect the adhesion of the coating after the material ages.

[0108] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details.

Claims

1. A dual anti-UV antireflective film, characterized in that, It includes an anti-UV optical film, an anti-UV curing coating formed on the surface of the anti-UV optical film, and a low-refractive-index anti-UV coating formed on the surface of the anti-UV curing coating; The UV-resistant curing coating is obtained by coating the surface of the UV-resistant optical film with a UV-resistant curing liquid and then curing it. The UV-resistant curing liquid comprises the following raw material components by weight: 6-12 parts by weight of acrylate monomers, 15-30 parts by weight of acrylic resin oligomers, 3-6 parts by weight of first inorganic particles, 60-80 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator. The low-refractive-index anti-UV coating is obtained by coating the surface of the anti-UV hardening coating with a low-refractive-index anti-UV liquid and then curing it. The low-refractive-index anti-UV liquid comprises the following raw material components by weight: 3-7 parts by weight of acrylate monomers, 5-11 parts by weight of fluorinated modified acrylic resin oligomers, 2-4 parts by weight of second inorganic particles, 100-200 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator.

2. The dual anti-UV antireflective film according to claim 1, characterized in that, The acrylic resin oligomer is a mixture of one or more of epoxy acrylate, polyurethane acrylate, polyester acrylate and polyether acrylate.

3. The dual anti-UV antireflective film according to claim 1, characterized in that, The first inorganic particle is one or a mixture of zirconium oxide or titanium oxide.

4. The dual anti-UV antireflective film according to claim 1 or 2, characterized in that, The acrylate monomers are one or a mixture of several of the following: trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trihydroxypropane tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and neopentyl glycol diacrylate.

5. The dual anti-UV antireflective film according to claim 1 or 2, characterized in that, The solvent is one or a mixture of several of ethyl acetate, n-butyl acetate, methyl isobutyl ketone, and isopropanol; The ultraviolet absorber is one or a mixture of several of the following: 2-(2ˊ-hydroxy-5ˊ-methylphenyl)benzotriazole, 2-hydroxy-4-methoxybenzophenone, 2,4,6-tris(2ˊn-butoxyphenyl)-1,3,5-triazine, 2-(2ˊ-hydroxy-3ˊ,5ˊ-di-tert-butylphenyl)-5-chlorobenzotriazole and 2,4-dihydroxybenzophenone; The light stabilizer is one or a mixture of several of the following: tris(1,2,2,6,6-pentamethylpiperidinyl) phosphite, 4-benzoyloxy-2,2,6,6-tetramethylpiperidin, and hexamethylphosphoric triamine. The photoinitiator is one or a mixture of 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and 1,1'-(methylenedi-4,1-phenylene)bis[2-hydroxy-2-methyl-1-propanone].

6. The dual anti-UV antireflective film according to claim 1, characterized in that, The second inorganic particle is a hollow mesoporous silica microsphere.

7. A method for preparing a dual anti-UV antireflective film as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Preparation of UV-resistant curing coating: Mix 6-12 parts by weight of acrylate monomers, 15-30 parts by weight of acrylic resin oligomers, 3-6 parts by weight of first inorganic particles, 60-80 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator, stir evenly to obtain UV-resistant curing coating liquid. S2. Apply the anti-UV curing liquid obtained in step S1 onto the anti-UV optical film, and after drying and UV curing, form an anti-UV curing coating on the anti-UV optical film. S3. Preparation of low refractive index UV-resistant coating: Mix 3-7 parts by weight of acrylate monomers, 5-11 parts by weight of fluorinated modified acrylic resin oligomers, 2-4 parts by weight of second inorganic particles, 100-200 parts by weight of solvent, 1-2 parts by weight of ultraviolet light absorber, 1-2 parts by weight of light stabilizer and 2-3 parts by weight of photoinitiator, stir evenly to obtain a low refractive index anti-UV coating liquid. S4. Apply the low-refractive-index anti-UV coating liquid prepared in step S3 onto the anti-UV hardening coating formed in step S2. After drying and UV curing, a low-refractive-index anti-UV coating is formed on the anti-UV hardening coating to obtain the double anti-UV antireflective film.

8. The method for preparing the dual anti-UV antireflective film according to claim 7, characterized in that, The UV-resistant optical film is selected from PET, PMMA, PC, TAC or SRF films with UV-resistant function; The thickness of the UV-resistant curing coating is 2~6μm, and the thickness of the low-refractive-index UV-resistant coating is 90~110nm.

9. The method for preparing the dual anti-UV antireflective film according to claim 7, characterized in that, The drying temperature in steps S2 and S4 is 90~110℃, and the drying time is 1~3min.

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